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Quality indicators in respiratory therapy
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作者 Manjush Karthika Sureshkumar Vanajakshy Kumaran Praveen Beekanahaali Mokshanatha 《World Journal of Critical Care Medicine》 2024年第2期116-125,共10页
Quality indicators in healthcare refer to measurable and quantifiable parameters used to assess and monitor the performance,effectiveness,and safety of healthcare services.These indicators provide a systematic way to ... Quality indicators in healthcare refer to measurable and quantifiable parameters used to assess and monitor the performance,effectiveness,and safety of healthcare services.These indicators provide a systematic way to evaluate the quality of care offered,and thereby to identify areas for improvement and to ensure that patient care meets established standards and best practices.Respiratory therapists play a vital role in areas of clinical administration such as infection control practices and quality improvement initiatives.Quality indicators serve as essential metrics for respiratory therapy departments to assess and enhance the overall quality of care.By systematically tracking and analyzing indicators related to infection control,treatment effectiveness,and adherence to protocols,respiratory care practitioners can identify areas to improve and implement evidence-based changes.This article reviewed how to identify,implement,and monitor quality indicators specific to the respiratory therapy departments to set benchmarks and enhance patient outcomes. 展开更多
关键词 Healthcare Quality indicators structurE PROCESS OUTCOME Respiratory therapy DEPARTMENT Respiratory therapists
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Evaluation Indicators and Extraction Method for Pitting Corrosion of Structural Steel 被引量:8
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作者 Shanhua Xu Youde Wang Qifeng Xue 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期15-21,共7页
A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extr... A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extract the evaluation indicators,the 3D profile data obtained by pitting morphology measurement are imported into a special written program to automatically determine the location of each corrosion pit and distill any desired data pertinent to the pitting morphology. The results show that this method seems to be effective to analyze the corroded surface and characterize the pitting morphology. 展开更多
关键词 structural steel pitting corrosion morphology characterization evaluation indicators extraction method
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Exploratory analysis of structural diversity indicators at stand level in three Italian beech sites and implications for sustainable forest management
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作者 Giada Bertini Claudia Becagli +3 位作者 Ugo Chiavetta Fabrizio Ferretti Gianfranco Fabbio Luca Salvati 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期121-127,共7页
The present study introduces an exploratory data analysis based on structural indicators with the aim to assess the effect of silvicultural practices on tree stand structure. The study was carried out in three Italian... The present study introduces an exploratory data analysis based on structural indicators with the aim to assess the effect of silvicultural practices on tree stand structure. The study was carried out in three Italian beech forests of different ages with stand structures that originated from dissimilar regeneration and cultivation techniques(Cansiglio, northern Italy, Chiarano, central Italy,and Mongiana, southern Italy). Ten structural indicators were considered when investigating the latent multivariate relationship between stand structure attributes before and after thinning operations by using a multiway factor analysis(MFA). The MFA results identified the older stand at Cansiglio as more homogeneous for cultivation regimes,and more stable to practices when compared with the younger sites(Chiarano and Mongiana). Heterogeneous stands were sensitive to silvicultural practice thus suggesting their possible impact on forest attributes. The proposed approach proved to be an operational tool to evaluate comprehensively the response of forest structure to planned interventions. 展开更多
关键词 Forest DIVERSITY Multiway factor analysis SILVICULTURE structural DIVERSITY indicatorS Tree STAND structure
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A Discussion on Possible Indicators Related to Genetic Structure Changes in Plant Germplasm Conservation 被引量:5
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作者 GAIJun-yi 《Agricultural Sciences in China》 CAS CSCD 2004年第11期869-880,共12页
The purpose of the present paper is to study and develop indicators and procedures for the evaluation of genetic structure changes in germplasm conservation due to social and natural environment reasons. Some basic ... The purpose of the present paper is to study and develop indicators and procedures for the evaluation of genetic structure changes in germplasm conservation due to social and natural environment reasons. Some basic concepts in germplasm study were introduced at first. Then, six kinds of indicators for genetic diversity as a measure of genetic potential of a germplasm collection were presented, i.e., numbers of different entities at certain level, evenness of the entity distribution, genetic similarity and genetic distance, genetic variance and genetic coefficient of variation, multivariate genetic variation indices, and coefficient of parentage. It was pointed out that genetic dispersion did not provide a complete concept of genetic diversity if without any information from genetic richness. Based on the above, the indicators for genetic erosion as the genetic structure changes of germplasm conservation due to social reasons, the indicators of genetic vulnerability as the genetic structure changes of germplasm conservation due to environmental stresses, the measurement of genetic drift and genetic shift as the genetic structure changes of germplasm collection during reproduction or seed increase were reviewed and developed. Furthermore, the estimation procedures of the indicators by using molecular markers were suggested. Finally, the case studies on suitable conservation sample size of self-pollinated and open-pollinated populations were given for reference. 展开更多
关键词 Genetic structure change Genetic diversity Genetic erosion Genetic vulnerability Genetic drift Genetic shift Statistical indicator
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Identifying Indicator Species in Habitats Created by Coastal Structures 被引量:1
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作者 Yi-Yu KUO Chun-Han SHIH +2 位作者 Ying-Chou LEE Wei-Tse CHANG Ta-Jen CHU 《China Ocean Engineering》 SCIE EI 2010年第1期117-134,共18页
In this paper, three approachs were developed to find indicator species from the habitat created by coastal structures. These approachs consist of a model of species co-occurrence probability, a model of k-environment... In this paper, three approachs were developed to find indicator species from the habitat created by coastal structures. These approachs consist of a model of species co-occurrence probability, a model of k-environmental factor probability and a composite model. Simultaneously, a case study was conducted in Hsinchu Fishing Port of north-western Taiwan. Based on the aforementioned models, three primary producer species, Ahnfeltiopsis flabelliformis, Chondrus ocellatus and Sarcodia montagneana, were chosen as the indicator species which had the highest co-occurrence probabilities and showed greater tolerance to more critical environment. It is imperative to understand how the three species under particular co-occurring conditions and environmental factors influence the composition of sessile assemblages in coastal water. The results indicate that for the purpose of increasing biodiversity, these models are feasible to find indicator species of artificial structures, and to help make it possible to design coastal structures based on biological considerations. This study provides an innovative approach for further advanced application in the artificial habitat of coast management. 展开更多
关键词 coastal structures indicator species sessile organisms ecological restoration
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Tree structure and diversity shape the biomass of primary temperate mountain forests
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Structural Characterization of Volatile Components of Rosa Banksiae Ait for Estimation and Prediction of Their Linear Retention Indices and Retention Times 被引量:6
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作者 朱万平 杨善彬 +2 位作者 廖立敏 谭超 舒茂 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期391-396,共6页
The molecular electronegativity-distance vector (MEDV) was used to describe the molecular structure of volatile components of Rosa banksiae Ait, and QSRR model was built up by use of multiple linear regression (MLR... The molecular electronegativity-distance vector (MEDV) was used to describe the molecular structure of volatile components of Rosa banksiae Ait, and QSRR model was built up by use of multiple linear regression (MLR). Furthermore, in virtue of variable screening by the stepwise multiple regression technique, the QSRR models of 10 and 6 variables and linear retention index (LRI) 10, 7 and 6 varieables were built up by combinating MEDV with the Ultra2 column GC retention time (tR) of 53 volatile components of Rosa Banksiae Air. The multiple correlation coefficients (R) of modeling calculation values of QSRR model were 0.906, 0.906, 0.949, 0.943 and 0.949, respectively. The cross-verification multiple correlation coefficients (RCV) were 0.903, 0.904, 0.867, 0.901 and 0.904, respectively. The results show that the models constructed could provide estimation stability and favorable predictive ability. 展开更多
关键词 molecular electronegativity-distance vector (MEDV) DESCRIPTOR quantitative structure-retention relationship (QSRR) linear retention indices (LRI)
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Two Network Structure Indicators for Conventional Public Transit
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作者 Min Fu Hao Wang +2 位作者 Wei Wang Sida Luo De Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期90-96,共7页
The significance of network structure indicators for the planning and management of conventional public transit is widely acknowledged.In order to improve and enrich the conventional public transit assessment system,t... The significance of network structure indicators for the planning and management of conventional public transit is widely acknowledged.In order to improve and enrich the conventional public transit assessment system,two network structure indicators are proposed.Firstly,according to the obvious defects lying in the traditional no-linear coefficient,the realistic no-linear coefficient γRNL,a modified no-linear coefficient indicator,is put forward,which takes into account the effects of barriers in a city.Secondly,to cover the gap of an indicator which can reflect the coverage homogeneity of a transit network,the length dimension LDis proposed on the basis of Fractal Theory.Finally,a case study is applied to verify the validity and practicability of the two indicators in problem diagnosis using regression analysis.The results validate that γRNLcan evaluate the detour of bus lines more reasonably than the previous no-linear coefficient because it reflects the layout of bus lines,and LDcan represent the rate of change of the network density,adding a new member to the scheme of network structure indicators for public transit. 展开更多
关键词 conventional public transit network structure indicator realistic no-linear coefficient length dimension fractal theory
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Structural Traits,Structural Indices and Body Weight Prediction of Arsi Cows
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作者 Aman Gudeto Tesfaye Alemu Aredo +1 位作者 Tadele Mirkena Sandip Banerjee 《NASS Journal of Agricultural Sciences》 2022年第1期33-40,共8页
Structural measurements are indicators of animal performance,productivity and carcass characteristics.This study was conducted with the objectives of assessing structural measurements,developing body weight prediction... Structural measurements are indicators of animal performance,productivity and carcass characteristics.This study was conducted with the objectives of assessing structural measurements,developing body weight prediction and structural indices for cows of Arsi breed.The cows were purchased from highland and lowland agro-ecologies of Arsi and East Shoa zones of Oromia regional state,Ethiopia and kept in Adami Tulu Agricultural Research Center(ATARC)for the breed development purpose.Totally 222 cows were included in the structural traits measurement.Thirty four young heifers were also considered in the study.Twenty two structural traits were considered during observational survey.The structural index was calculated from the phenotypically correlated linear measurements.Structural traits were analyzed by T-test of SPSS version twenty four.The observed average values of height at wither,chest depth,heart girth,body length,pelvic width,cannon bone circumferences of the cows were 107,55.62,141.06,117.82,31.41 and 13.58cm,respectively.Heart girth(0.82),flank girth(0.73),hook circumferences(0.67),chest depth(0.65)and height at rump(0.64)were highly correlated(P<0.01)to body weight of the cows.Regression analysis indicated that hearth girth had the highest coefficient of determination for body weight of the cows and heifers.Accordingly,the simple linear equations were developed to predict the body weight of cows and heifers.Body weight of Arsi cow(y)=-221.005+3.1(heart girth)and Body weight of Arsi heifer(y)=-188.452+2.75(heart girth).Based on this,the measuring chart tape can be developed to estimate the body weight of Arsi cows and heifers at field condition where there is no access to weighing scales. 展开更多
关键词 Cattle structural traits Arsi cows structural indices Body weight prediction
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A Quantitative Structure Property Relationship for Prediction of Flash Point of Alkanes Using Molecular Connectivity Indices 被引量:3
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作者 Morteza Atabati Reza Emamalizadeh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期420-426,共7页
Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecul... Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecular structure without any experimental effort, they provide a simple and straightforward method for property prediction. In this work the flash point of alkanes was modeled by a set of molecular connectivity indices (Х), modified molecular connectivity indices ( ^mХ^v ) and valance molecular connectivity indices ( ^mХ^v ), with ^mХ^v calculated using the hydrogen perturbation. A stepwise Multiple Linear Regression (MLR) method was used to select the best indices. The predicted flash points are in good agreement with the experimental data, with the average absolute deviation 4.3 K. 展开更多
关键词 quantitative structure property relationship flash point molecular connectivity indices hydrogen perturbation ALKANE
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Damage Assessment of Reinforced Concrete Structures through Damage Indices:A State-of-the-Art Review 被引量:2
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作者 D.A.Makhloof A.R.Ibrahim Xiaodan Ren 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第9期849-874,共26页
Due to the developments of computer science and technology in recent years,computer models and numerical simulations for large and complicated structures can be done.Among the vast information and results obtained fro... Due to the developments of computer science and technology in recent years,computer models and numerical simulations for large and complicated structures can be done.Among the vast information and results obtained from the analysis and simulations,the damage performance is of great importance since this damage might cause enormous losses for society and humanity,notably in cases of severe damage occurring.One of the most effective tools to handle the results about the damage performance of the structure is the damage index(DI)together with the damage states,which are used to correlate the damage indices with the damage that occurred in the actual structures.Numbers of damage indices proposed and developed rely on the fact that the damage causes noticeable changes in the structural and dynamic properties of the structural components or the whole structure.Therefore,this study presents a comprehensive review of the damage assessment of Reinforced Concrete(RC)structures.It presents step by step the development of the damage indices that are most widely used to estimate the performance of structural components in the structure and subsequently assess the damage degree of such these structures either based on the structural properties or dynamic properties of the structure.Also,several damage states have been introduced to estimate the performance level of the structure.Finally,case studies,methodologies,and applications on the damage assessment of RC structures are reviewed and presented. 展开更多
关键词 structure properties-based damage indices dynamic properties-based damage indices damage states
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Lithostructural controls in Douala-Buea Region landscape (SW Cameroon margin):Insights from morphometric analysis 被引量:1
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作者 Christian BALLA ATEBA Sébastien OWONA +3 位作者 Moussa NSANGOU NGAPNA Véronique MANGA TSIMI DieudonnéMINYEM Joseph MVONDO ONDOA 《Journal of Mountain Science》 SCIE CSCD 2021年第1期68-87,共20页
The Douala-Buea Region(DBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimenta... The Douala-Buea Region(DBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimentary cover,was explored in order to evaluate the lithology and tectonics controls on its landscape usingthequalitativeandquantitative geomorphological analyses based on 30 m resolution Digital Elevation Models(DEM)and field evidences.This area displays an uneven and complex landscape differentiated into four morphological units:Douala,Nkondjock,Kumba and Buea Units.The Douala Unit corresponds to the Coastal Plain and is extended on the Douala-Kribi/Camposedimentarybasin.The Nkondjock Unit represents a middle plateau developed on a Proterozoic granito-gneissic basement.The Kumba Unit matches with the southernmost volcanic Western Cameroon High Plateau.The Buea Unit corresponds to the Mount Cameroon stratovolcano.The relief analysis through mountain-front sinuosity(Smf,1.19–1.43)and relative relief ratio(Rr,0.10–2.31)vary from one unit to another.The drainage network analysis including drainage patterns,stepped longitudinalriverprofiles,theassociated morphometric indexes,notably the concavity index(IC,0.56–0.88),deviation(D,267–2912 m),basin asymmetry factor(A_(F),6.37–42.12),hypsometric integral(HI,0.10–0.29),valley floor width to valley height ratio(V_(f),0.36–2.75),elongation ratio(R_(e),0.30–0.50),watershed slope(S,6.88–88.88)and stream length gradient index(SL,0–3332)vary from one basin to another too.These results also show the heterogeneous and uneven DBR landscape controlled by its lithology and active tectonics.The drainage system reveals concave to concavo-convex longitudinal river profile shapes with knick points,asymmetric basins,and fault reactivations,and highlights the tectonics activity that used to occur through the time and their control on the morphology.Together,they document the lithostructural controls on the DBR landscape evolution,extendable in the whole SW Cameroon margin. 展开更多
关键词 Morphometric indices Lithological control structural control Morphological units Douala-Buea Region SW Cameroon margin
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Floristic diversity and structural parameters of the Brazzaville Patte d’Oie forest, Congo
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作者 Victor Kimpouni Paul Mbou +1 位作者 Ernest Apani Marcel Motom 《Open Journal of Ecology》 2013年第8期518-531,共14页
The flora of the Patte d’Oie forest of Brazzaville is studied according to three plots of 0.5 ha, corresponding each to one of the islet, currently constituting it. With an original area of 240 ha, put in reserve in ... The flora of the Patte d’Oie forest of Brazzaville is studied according to three plots of 0.5 ha, corresponding each to one of the islet, currently constituting it. With an original area of 240 ha, put in reserve in 1938, the natural forest of the Patte d’Oie of Brazzaville covers 95 ha, less than 39% compared to initial area. Because the other main forests of Brazzaville have disappeared without delivering their biodiversity, this study is the first one which emphasizes the flora of this single ecosystem of Congo. The total floristic inventory revealed 459 trees of dbh≥10 cm on 1.5 ha;it is an average of 306 trees?ha?1. 31 species are listed for 17 families, and the best represented of which (Fabaceae, Euphorbiaceae and Rubiaceae) have a diversity varying from 13% to 19% of the inventory and a tree number oscillating from 15% to 36%. The Shannon (H') biological diversity index of the three plots is of 2.6 on average, for a maximum diversity (H'max) average of 2.9 versus an average true diversity of 15. The Pielou index is on average 0.9, whereas that of Simpson is 0.9. The coefficients of similarity of Jaccard (41.4% to 57.1%) and of the coefficient of S?rensen (58.5% to 72.7%) show the variations in the floristic composition. The followed ecological parameters show that this ecosystem is very few diversified compared to the tropical wet dense forests on the one hand, and, on the other hand, a non constant floristic composition is not. The analysis of the diametric structure by plot and the dominant and/or characteristic species give erratic curves, evidence of an insufficiency of the regenerative potential. Indeed, approximately 70% of the species are characteristic of the disturbed ecosystems (Macaranga sp.,Caloncoba welwitschii,Hymenocardia ulmoides,and Anthocleista sp.). 展开更多
关键词 CONGO FLORISTIC DIVERSITY Biological DIVERSITY indices Population structure Urban FOREST RESERVE
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Some Structural Properties of Dynamically Drawn iPP Fibers
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作者 Afaf M. Ali 《Optics and Photonics Journal》 2017年第6期109-121,共13页
Changes in the different structural parameters of iPP fibers during the dynamically cold drawing process were characterized. Using the dynamic mechanical cold drawing device attached to Fizeau interference system all ... Changes in the different structural parameters of iPP fibers during the dynamically cold drawing process were characterized. Using the dynamic mechanical cold drawing device attached to Fizeau interference system all the optical and structural properties can be measured. With the aid of this device the effect of the strain rate on the different structure properties was measured. The molecular orientations, molecular polarizability, molar reflectivity and shrinkage stress were measured. Reorientation of the molecules led to a significant variations in the measured structure properties of the drawn iPP fibers during applying the external tension. 展开更多
关键词 DRAWING structural ORIENTATIONS and Refractive indices
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Using DEA and AHP for Multiplicative Aggregation of Hierarchical Indicators
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作者 Mohammad Sadegh Pakkar 《American Journal of Operations Research》 2015年第5期327-336,共10页
The author [Pakkar, M.S. (2014) Using Data Envelopment Analysis and Analytic Hierarchy Process to Construct Composite Indicators. Journal of Applied Operational Research, 6(3), 174-187.] recently proposed a multiplica... The author [Pakkar, M.S. (2014) Using Data Envelopment Analysis and Analytic Hierarchy Process to Construct Composite Indicators. Journal of Applied Operational Research, 6(3), 174-187.] recently proposed a multiplicative approach using Data Envelopment Analysis (DEA) and Analytic Hierarchy Process (AHP) to reflect the priority weights of indicators in constructing composite indicators (CIs). Nonetheless, this approach is limited to the situations with a single level hierarchy which might not satisfy the needs of a multiple level hierarchy. Therefore, the current paper extends this approach to the situations in which the indicators of similar characteristics can be grouped into sub-categories and further linked into categories to form a three-level hierarchical structure. An illustrative example of road safety performance for a set of European countries highlights the usefulness of the proposed “extended approach”. 展开更多
关键词 Data Envelopment Analysis ANALYTIC HIERARCHY Process Composite indicatorS MULTIPLICATIVE AGGREGATION HIERARCHICAL structures
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Structural Model of Strengths and Virtues on Basis of Positive Psychology
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作者 Zhan Qisheng Liu Yuanyuan +2 位作者 Su Huili Zhang Kuo Feng Chuande 《Psychology Research》 2014年第3期193-200,共8页
关键词 结构模型 心理学 美德 基础 优势 拟合指数 影响因素 调查结果
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浮游生物对渭河水环境的响应机理及生态效应 被引量:1
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作者 孙亚乔 蒋婕 +6 位作者 段磊 杨思月 周艾诗 朱思衡 曹永翔 孙佳乾 寇思飞 《水利水电技术(中英文)》 北大核心 2024年第4期121-136,共16页
【目的】为探究浮游生物对渭河陕西段水环境的响应机理及生态效应,【方法】以渭河陕西段为研究区,于2021年4月共设置14个采样点,采集14份水样,分析浮游生物群落结构空间分布特征;评估浮游生物群落的均匀性、物种丰富度和多样性时,常用Pi... 【目的】为探究浮游生物对渭河陕西段水环境的响应机理及生态效应,【方法】以渭河陕西段为研究区,于2021年4月共设置14个采样点,采集14份水样,分析浮游生物群落结构空间分布特征;评估浮游生物群落的均匀性、物种丰富度和多样性时,常用Pielou指数、Margalef指数和Shannon-Weiner指数,并评价断面水环境质量;利用典范对应分析(CCA)和冗余分析(RDA)识别环境因子对浮游植物和浮游动物群落空间分布的影响程度。【结果】结果表明:渭河陕西段浮游植物共有7门55种,硅藻门种类数最多(49.09%),优势种有6种;浮游动物共3门22种,轮虫占比最高(68.18%),优势种有4种;浮游植物的H′、J及d变化范围分别为1.017~4.025、0.267~0.890、0.446~1.099,浮游动物其指数变化范围分别为0.811~2.459、0.754~1.000、0.126~0.542;CCA分析显示,影响浮游植物群落空间分布变化的环境因子主要有TP、NH_(3)-N和pH;根据RDA分析结果显示,对于浮游动物群落结构的主要影响因子,化学需氧量(COD)和水温(WT)起到了关键作用。【结论】结论显示:渭河陕西段浮游生物指数变化显示研究区域呈现清洁—中污染状态;根据《中国淡水藻类—系统、分类及生态》《环境和指示生物(水域分册)》中浮游植物和浮游动物的水污染指示物种判断水环境状况,对比本研究浮游植物和浮游动物的多样性指数评价水环境质量,得出浮游动物对水质评价的响应结果更加准确。通过构建水环境-浮游生物对比判断模型,选择区域更加准确的评价指标,有助于提高浮游生物对水生态环境指示作用的准确性,进而揭示浮游生物对水生态环境的响应机理。以上结果可为渭河流域水生态环境保护提供理论参考。 展开更多
关键词 浮游植物 浮游动物 指标识别 群落结构 生物多样性 水质
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基于超声诊断对中老年食蟹猴心脏结构和功能的基础研究
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作者 刘书华 周丹 +7 位作者 陈洪毅 李韵峰 黄忠强 关雅伦 吴昌林 李雪娇 李舸 张钰 《中国实验动物学报》 CAS CSCD 北大核心 2024年第7期856-866,共11页
目的 针对10岁以上中老年食蟹猴开展心脏结构和功能基础研究,为研究老年疾病动物选择提供基础数据。方法 本研究选取144只10岁以上中老年食蟹猴作为研究对象,分为10~15岁组雌性37只、雄性66只,16~20岁组雌性21只、雄性20只,通过一般指标... 目的 针对10岁以上中老年食蟹猴开展心脏结构和功能基础研究,为研究老年疾病动物选择提供基础数据。方法 本研究选取144只10岁以上中老年食蟹猴作为研究对象,分为10~15岁组雌性37只、雄性66只,16~20岁组雌性21只、雄性20只,通过一般指标(身体质量指数、血压、心率)、血液生化指标(血糖、血脂和离子指标)、心脏结构和功能指标比较分析,获得中老年食蟹猴心脏结构和功能相关基础数据。结果 10~15岁组和16~20岁组,一般指标比较,随着年龄增加,雌猴和雄猴血压和心率升高,雄猴血压变化具有显著性差异。两组血液生化指标比较,随着年龄增加,雌猴和雄猴血糖、甘油三酯、总胆固醇、低密度脂蛋白胆固醇、血钙、血钠、血钾都显示升高,其中,血糖、甘油三酯(雄)、总胆固醇、高密度脂蛋白胆固醇(雄)、低密度脂蛋白胆固醇(雄)、血钙、血钠、血钾变化具有显著性差异;乳酸脱氢酶显示下降,具有显著性差异。两组心脏收缩功能比较,随着年龄增加,雌猴和雄猴左房前后内径都下降,具有显著性差异;雌猴室间隔收缩末径,左心室舒张和收缩末径显示减小,左心室舒张末容积,左心室收缩末容积,左心室质量指数下降,具有显著性差异,雄猴变化不显著。两组心脏舒张功能比较,随着年龄增加,雄猴二尖瓣舒张晚期速度下降,具有显著性差异;雌猴左室侧壁舒张早期速度升高,具有显著性差异。对雌猴和雄猴代谢指标与心脏结构和功能指标进行相关性分析,结果雌猴代谢指标与心脏结构和功能指标的相关性较弱,Γ绝对值最高不超过0.39,雄猴代谢指标与心脏结构和功能指标的相关性相对较强,Γ值绝对值最高达到0.66。结论 基于超声诊断结合代谢指标对食蟹猴心脏功能进行研究,建立中老年食蟹猴心脏结构和功能相关指标基础数据,随着年龄的增加,食蟹猴的血糖、血脂指标升高,心脏收缩和舒张功能有下降趋势,与中老年人群变化相似,为开展心脏功能相关的老年性疾病研究动物选择提供数据支撑。 展开更多
关键词 中老年食蟹猴 心脏结构和功能指标 血液生化指标 一般指标
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邯郸地区不同类型高温大曲细菌群落与理化特性差异性分析
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作者 王玉荣 侯强川 +5 位作者 田龙新 张振东 黄利科 孔金钊 郝光飞 郭壮 《现代食品科技》 CAS 北大核心 2024年第10期136-145,共10页
该研究采用高通量测序技术对不同类型高温大曲细菌群落进行了解析,继而对其理化指标进行测定,同时对2者的相关性进行分析,最后使用纯培养技术对细菌资源进行挖掘。测序结果表明,黄色高温大曲中Thermoactinomyces、Limosilactobacillus和... 该研究采用高通量测序技术对不同类型高温大曲细菌群落进行了解析,继而对其理化指标进行测定,同时对2者的相关性进行分析,最后使用纯培养技术对细菌资源进行挖掘。测序结果表明,黄色高温大曲中Thermoactinomyces、Limosilactobacillus和Weissella的平均相对含量显著偏高(P<0.05),分别为21.04%、14.30%和3.15%,Lentibacillus和Kroppenstedtia的平均相对含量显著偏低(P<0.05),分别为3.30%和2.81%,而其在黑色高温大曲中分别为1.93%、0.036%、0.027%、34.45%和20.75%。此外,LEfSe分析发现Thermoactinomyces和Lentibacillus可分别作为黄色和黑色高温大曲的生物标志物。理化指标测定显示,黄色高温大曲的水分含量、液化力、糖化力、酯化力和酒化力显著偏高(P<0.05),而酸度显著偏低(P<0.05)。相关性分析发现,优势细菌属与理化指标之间存在显著相关性(P<0.05)。采用纯培养技术从高温大曲样品中共分离得到33株细菌菌株,鉴定为5个属的10个种,主要以Bacillus为主,且B.licheniformis为优势分离株,占分离株总数的30.30%。由此可见,2种类型高温大曲细菌群落与理化指标间均存在明显差异,且微生物与理化指标之间具有一定相关性。 展开更多
关键词 高温大曲 细菌群落结构 理化指标 分离鉴定
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重叠社区发现算法评价指标综述
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作者 韩红旗 徐紫燕 +1 位作者 李琳娜 周则旭 《计算机技术与发展》 2024年第5期1-9,共9页
重叠社区发现算法对于理解复杂系统、发现复杂网络中隐藏的规律等具有很强的应用价值,而评价指标是算法发现高质量重叠社区的一个关键要素,算法的进步常常依赖于评价指标的进步。现有研究对非重叠社区发现算法的评价指标有较多的总结,... 重叠社区发现算法对于理解复杂系统、发现复杂网络中隐藏的规律等具有很强的应用价值,而评价指标是算法发现高质量重叠社区的一个关键要素,算法的进步常常依赖于评价指标的进步。现有研究对非重叠社区发现算法的评价指标有较多的总结,而没有对重叠社区发现算法的评价指标进行总结。对重叠社区发现算法的评价指标进行了系统的总结和回顾,将指标分为事先知道社区结构、事先不知道社区结构和其它三大类。事先知道社区结构的评价指标包括基于混淆矩阵、基于ARI、基于NMI三个子类评价指标,事先不知道社区结构的评价指标包括基于模块度、基于密度、基于元数据三个子类评价指标,其它类主要介绍算法可扩展性评价指标。深入理解各种评价指标对于开发和优化重叠社区发现算法、在实际应用中发现高质量社区具有重要价值。 展开更多
关键词 重叠社区 评价指标 社区发现 社区结构 复杂网络
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